Two prior surveys of health sciences libraries resulted in publication of the Directory of Health Sciences Libraries in the United States, 1969, and the Directory of Health Sciences Libraries in the United States, 1973. The continuing growth of libraries has rendered these publications obsolete. The specific objective is to design, implement, execute and publish the results of a Third Health Sciences Library Survey, which will provide data essential for the description and assessment of the nature, extent and adequacy of health sciences library resources and services in the United States. The universe surveyed will be some 14,000 health related institutions--hospitals, medical schools, local, state and federal government agencies, training programs in the allied health professions and group practice clinics. In addition, at the request of the National Research Council of Canada, 2000 Canadian institutions will be included. Questionnaires will be mailed to this universe to gather the maximum amount of data concerning library facilities, resources, services and usage. The resulting data will be keypunched and inputted to a computer for sorting, merging, editing and formatting by means of computerized photo-composition to produce high quality camera-ready copy. 2000 copies of the Third Directory of Health Sciences Libraries in the United States and Canada, 1978 will be printed, announced and sold. The target audience of the publication consists of the major health sciences libraries, regional medical libraries, networks and consortia and organizations concerned with the planning, development and funding of health sciences library resources and services. It is anticipated that statistical analyses will result in the publication of a monograph or special issue of the Bulletin of the MLA. An Advisory Committee for the project will consist of representatives of AMA, AHA, ADA, AAMC, NCES, and NLM.